Time Critical Removal Action, Former Kingman Ground-to-Ground Gunnery Range Kingman, AZ (FUD)

USACE Los Angeles Eco was contracted by the U.S. Army Corps of Engineers (USACE) to complete a Time Critical Removal Action (TCRA) at eleven (11) parcels on the former Kingman Ground-to-Ground Gunnery Range in Kingman, Arizona that was used during World War II for aerial gunnery training. The TCRA was necessitated as a result of sampling results at the site during the Site Investigation (SI) phase of the project. In a part of the property, clay pigeon debris was observed scattered at the surface. The soil in this area contained polycyclic aromatic hydrocarbons (PAHs) that represented unacceptable risk to the residents. The performance of the TCRA involved community involvement and related meetings including relocation of residents and any pets or livestock present on the subject property. By removal of the soil to a depth of two feet and replacing the removed soil with clean fill, the potential exposure of the residents to the high-PAH soil was mitigated. Eco completed TCRA at eleven (11) lots. A risk screening analysis was performed for all parcels. This parcel was projected at below the regulatory thresholds for non-carcinogenic hazards, carcinogenic risks, and lead exposure levels. Furthermore, the removal of the upper two feet of contaminated surface soil within the parcel essentially eliminated the current exposure pathway. The screening risk analysis demonstrated, in a conservative manner, that the conditions at the subject parcel no longer required TCRA efforts and that residual contamination could be effectively addressed in the future Remedial Investigation and Feasibility Study (RI/FS) stage of the project. Eco completed the TCRA under the oversight of the Arizona Department of Environmental Quality (ADEQ)-approved Work Plan. A concurrent RI/FS, which came in a contract modification outside the scope of this TCRA, was conducted by Eco to determine the nature and extent of the PAHs, lead, and other metals in the on-site soils throughout the site.